P100. Factors Affecting the Cervical Space Available for the Cord in Klippel-Feil Patients

Autor: Dino Samartzis, Jean Herman, John P. Lubicky, Prakasam Kalluri, Francis H. Shen
Rok vydání: 2006
Předmět:
Zdroj: The Spine Journal. 6:132S
ISSN: 1529-9430
Popis: BACKGROUND CONTEXT: Klippel-Feil syndrome (KFS) is a developmental disorder presenting with congenital fusion of at least 2 cervical segments. Due to the altered biomechanics associated with fused segments, previous studies have suggested that KFS patients are possibly predisposed to segmental degenerative and/or stenotic alterations that could directly affect the neural elements. However, a large majority of KFS patients remain asymptomatic. Overall, studies have failed to address the effects that various factors associated with KFS have upon the neural elements, specifically the space available for the cord (SAC), and associated cervical spine-related symptoms. PURPOSE: To evaluate in KFS patients various factors of cervical motion, fusion patterns, geometric parameters, and the development of cervical spine-related symptoms (CSRS) in association with the SAC. STUDY DESIGN/SETTING: A retrospective review at a single institution. PATIENT SAMPLE: Twenty-six KFS patients. OUTCOME MEASURES: Fused cervical segments were identified by lateral neutral, flexion, and extension plain radiographs. SAC was evaluated on lateral radiographs and consisted of the posterior atlantodens interval (PADI), and at the level of the pedicle and the intervertebral disc (IVD) from C2-T1. Vertebral body width (VBW) was noted from C2-C7. Degree of scoliosis and dynamic sagittal alignment were assessed. Demographics, medical history, and the development of CSRS (headaches, radiculopathy, myelopathy) were noted based on clinical chart review. METHODS: Radiographic and clinical assessments were evaluated separately by 2 independent blinded observers. The threshold for statistical significance was p!.05. RESULTS: Radiographic and clinical reviews were conducted in all 26 patients (10 males, 16 females; mean age, 14 years). The mean number of levels fused was 3.7. The most commonly fused segments were C2-C3 (69.2%), C5-C6 (69.2%), and C6-C7 (65.4%). Occipitalization occurred in 34.6% of the patients. A mean PADI value of 20.25 mm was obtained. Overall mean SAC at the pedicle and IVD was noted as 15.7 mm and 15.3 mm, respectively. A mean of 16.1 degrees of scoliosis was noted. The mean sagittal alignment at neutral, flexion, and extension was noted as 40.7, 7.8, and 64.7 degrees, respectively. Age, sex, and sagittal alignment were not statistically significant factors related to the SAC (pO.05). As the number of fused levels increased, so did the degree of scoliosis (p5.069). A significant positive correlation was noted between the degree of scoliosis and the SAC (p!.05; r50.405 to 0.557). Each fused segment exhibited smaller VBWs in comparison to nonfused segments, with significant difference involving C2-C3 and C6-C7 (p!.05). An overall statistically significant difference between the presence of fusion and the size for the SAC was not noted at each level, with the exception of C2-C3 where the SAC was dramatically larger (p!.05). The fused levels of C2-C3, C3-C4, and C6-C7 did exhibit an increased trend in SAC in the presence of fusion. Symptoms were noted in 30.8% of patients, of which 37.5% stemmed from a traumatic episode. No statistically significant difference was noted between the presence of symptoms and patient demographics, SAC, number of levels fused, or motion parameters (pO.05). CONCLUSIONS: Due to the congenital fusion process in KFS, a tapering effect or decreased width of the vertebral body morphology is noted, which may allow an increase in size for the SAC. Such a development may delay neurologic compromise stemming from degenerative manifestations. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. CONFLICT OF INTEREST: No conflicts.
Databáze: OpenAIRE
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